Macbeths stability of mind:

Macbeth’s mind is not very stable at all. Before killing Duncan he has all these thoughts in his head and tall this causes his mind to become unstable. He starts to see illusions like the dagger floating in air. Referring back to an often said quotation “foul is fair and fair is foul.” Again, it means that what you see is real isn’t really real and that what isn’t really real is real. "A dagger of the mind, a false creation, proceeding for the heat oppressed brain". Here Macbeth is experiencing what might be a moral crisis. He knows he is about to kill Duncan, but he is imagining what it will be like to actually hold the dagger and carry out the act. Macbeth is properly horrified by his vision, but then a ringing bell snaps him back to reality and he feels refreshed to resolve and fulfill his plan. Another good example would be where he sees the ghost of Banquo. Also while sleeping he has a nightmare that Banquo and Fleance are killing him when he is sleeping just like when he killed Duncan in his sleep; and a while before that when he killed Duncan and the next morning kills the chamberlains because he couldn’t stand seeing the dead body of Duncan. The Chamberlains were low class and couldn’t ever be trusted, so they would have died one way or another. That was another mistake he made because of his unstable mind.